1. Field of the Invention
The invention relates to a closing device for closing functions to be performed especially on vehicles, with a closing cylinder, wherein the closing cylinder comprises a free bushing and a cylinder core supported therein axially fixed and rotationally and having a cylinder portion comprising followers, and the followers are controllable by insertion of a key and, when the key is removed, lock the cylinder core with the free bushing, with a stationary housing receiving the free bushing in a rotatable fashion in which, however, the free bushing is normally rotationally fixed by a radially spring-loaded locking and control member of an overload interlock, wherein the locking and control member is positioned loose in a radial recess of the housing and, in the normal situation, engages with its radially inner end, because of the radial spring load, a radial recess of the free bushing having a lifting profile, wherein, however, in the overload situation, it moves from this engagement position, counter to its spring load, into a lifted position in the circumferential area of the free bushing, with a working member performing the locking function in the vehicle as well as with a slide rotationally fixedly but slidably connected with the working member, which normally is in a rotationally fixed coupling position with the cylinder core because of a return force, but in the overload situation is decoupled by means of the locking and control member and reaches a locking position which is rotationally fixed in the housing, in which optionally also the working member is locked. When the proper key is completely inserted into the cylinder core and the key is turned, the rotation is transmitted in this device onto a working member which acts on the lock and performs thereat closing functions. When a forced rotation of the closing cylinder by means of burglary tools is carried out, an overload interlock ensures that, even though a rotation of the cylinder core together with the free bushing takes place, this rotation is not transmitted onto the working member. Accordingly, a closing function is not carried out. Moreover, in the overload situation manipulations on the working member are also not possible because they are secured in a locking position; it is secured in the housing. This overload safety ensures that the device is not damaged in the case of forced opening attempts by burglary tools. The device is subsequently ready to be actuated by means of a proper key in the proper way.
2. Description of the Related Art
Devices of the aforementioned kind (DE 44 12 609 A) have been successful in practice but they have the disadvantage of a relatively large axial constructive length. In this device, the overload interlock must be arranged in an axial extension of the cylinder core which is arranged behind the cylinder portion which comprises the followers. The slide is arranged in a recess of the working member which is formed as a lever. In the recess a pressure spring must also be arranged which is supported between the slide and the working member and generates the radial spring load for the locking and control member of the provided overload interlock. The spring load of the overload interlock is thus realized indirectly via the slide. For space reasons, the pressure spring can be only small so that its radial spring load is limited. In order to be able to activate this spring load, the slide has an axial tab which is supported on the locking and control member. The supported tab of the slide is positioned in the same portion as the locking and control member. Moreover, in the same axial portion, the locking surfaces between a locking tongue and an outer sleeve of the housing are provided and, finally, also an inner sleeve of the housing with the radial recess for the locking and control member. The known device has, in addition to the overload interlock, also a catch member in the form of a roller which is forced by a leaf spring into a catch recess of the free bushing. This catch member was axially remote from the overload interlock and could not perform a control function on the slide. The known device was space-intensive and could not exert a sufficiently high spring-load onto the overload interlock.
It is an object of the invention to develop a reliable, space-saving device of the aforementioned kind which is primarily characterized by a minimal axial construction length. This is achieved according to the invention in that the radial recess for the locking and control member is open toward the exterior of the housing and the locking and control member is exposed in the radially outward direction, but is covered by a leaf-shaped spring, wherein the spring is arranged in the circumferential area of the housing and acts directly on the locking and control member, that the control and locking member is arranged radially adjacent to the cylinder portion of the cylinder core being provided with the followers, and that the slide is positioned in a portion of the closing cylinder axially stepped relative to the locking and control member and that an axial connection bridges the spacing between the locking and control member and the slide. According to the invention, the locking and control member can be arranged independently of the location of the slide and can therefore be arranged without problems in that cylinder portion of the cylinder core where also the followers are positioned. This saves axial space within the device. In this cylinder portion the locking and control member is radially outwardly exposed and is covered by a leaf-shaped spring which exerts directly the radial spring force of the overload interlock onto the locking and control member. The slide can be axially remote from the locking and control member. The spring load of the overload interlock which now acts independently of the slide can be as large as desired depending on a corresponding size of the leaf-shaped spring. Moreover, it is now also possible without problems to activate by the same or a separate leaf-shaped spring several locking and control members in the overload interlock, for example, a diametrically correlated pair of members. The spring load of the leaf-shaped spring which acts directly onto the locking and control member is used according to the invention for controlling the slide. For this purpose, an axial connection is provided which bridges the spacing between the side and the locking and control member. This axial connection can be formed in different ways, wherein each of these possibilities has its own inventive importance.
A first possibility for this axial connection resides in that a control member produces an indirect axial connection between the locking and control member and the slide, wherein the control member is arranged radially outside of the housing and connected to a spring of the overload interlock acting on the locking and control member and is moveable together with it. The control member is arranged radially outside of the housing and is formed either as a unitary part of the leaf-shaped spring acting on the locking and control member or comprised of several parts that are however connected to form a constructive unit. When the locking and control member in the overload situation is lifted out of the radial recess of the free bushing, the control member and the spring perform a common radial movement, and this movement is transmitted via the control member onto the slide.
A second possibility for the axial connection resides in that between the locking and control member and the slide a direct positive-locking connection is realized and that the spring of the overload interlock acting on the locking and control member produces by the positive-locking action at the same time the return force which forces the slide into the coupling position with the cylinder core. A direct positive-locking connection between the locking and control member and the slide is provided. In this case, the spring acting on the locking and control member has a double function. On the one hand, it serves as a radial spring-load of the overload interlock, as mentioned above. By means of the positive locking connection, the spring however has at the same time the new function of generating the return force, already mentioned above, which secures the slide in its coupling position. By means of this positive locking connection, the slide is transferred into a locking position in the overload situation in which the slide is fixed in the housing and, at the same time, the working member is secured in the housing. An especially simple embodiment of this positive-locking connection between the slide and the locking and control member results when the positive-locking connection is comprised of an axial pin on the locking control member and a link guide in the slide wherein the pin engages the link guide.